Radio selector switch and dial mechanism



Jan, 6, 1953 w. P. LEAR 2,624,835

RADIO SELECTOR SWITCH AND DIAL MECHANISM Filed Sept. 5, 1948 2SHEETSSHEET 1 Nroza.

Lear

Jan. 6, 1953 w. P. LEAR 2,624,335

RADIO SELECTOR SWITCH AND DIAL MECHANISM Filed Sept. 3, 1948 2 swam-saw:2

IN V EN TOR.

ZUz lZz'a/rz R Zear BY Patented Jan. 6, 1953 RADIO SELECTOR SWITCH ANDDIAL MECHANISM William Powell Lear, Santa Monica, Calif., as-

signor to Lear, Incorporated, Grand Rapids, Mich, a corporation ofIllinois Application September 3, 1948, Serial No. 47,624

Claims.

This invention relates to a combined function selector switch and tuningmechanism for a radio receiver or similar instrument.

For certain types of multi-band radio receivers, for example, as used inaircraft, there has been provided a band selector switch and a functionselector switch, each independently operable by separate knobs or thelike. The function selector switch may be used for switching betweenantennas, for voice reception, radio ranging and other uses, and all orcertain ones of these functions are desirable on one or more bands andnot on others. However, it is desirable that the two knobs or handlespreviously required be combined into a single control, particularly inradio equipment intended for use aboard aircraft. It will be recognizedthat minimizing of the number of separate controls is a desirableobjective in any type of apparatus, and especially so for an airplanepilot, whose task is complicated to a degree in the primary manipulationof the craft. Moreover, since it is possible to so arrange the receiverthat certain functions be associated with certain bands and not others,the element of automatism inherent in single-knob control is a decidedadvantage.

Accordingly the primary object of my invention is to provide in a radioequipment means for selecting a desired frequency band, together withmeans for selection of functions while operating within one or morespecific bands, said bandand function-selecting operations beingoperable by a single handle or knob.

Another object is to provide combined means as aforesaid which includesdevices for accurately positioning the movable parts and for preventinginadvertent dislodgment thereof from a selected position.

Generally the invention comprises a selector switch for modifying thecircuitry of the apparatus to enable it to respond to one of a pluralityof frequency bands of the operators selection, the switch includingcontacts for maintaining operation in the selected band while insertingor removing other components in and from the circuit. Means are providedfor manipulating a shutter juxtaposed to the tuning dial for exposinggraduations on the dial corresponding to the selected frequency band,these means being cojointly operable with the band selector switch.Rotation of the tuning dial and tuning means, e. g. variable condensers,is by means of one knob, and operation of the remaining described mechanism by a second knob.

In the drawings which show one preferred mode of embodying the inventionin practice:

Fig. 1 is a front elevational view of the receiver with the frontescutcheon plate removed;

Fig. 2 is a plan view of the receiver showing those parts thereofembodying the invention, some cooperating parts in phantom, and otherinconsequential parts eliminated;

Fig. 3 is a view similar to Fig. l but with the front escutcheon platein place;

Fig. 4 is a perspective detail of the rack guide;

Fig. 5 is a cross sectional detail taken on the line 55 of Fig. 1;

Fig. 6 is a cross sectional detail taken on the line 65 of Fig. 1;

Fig. '7 is a detail of the tuning dial;

Fig. 8 is a detail view of the rack and rack retaining spring; and

Figs. 9 to 14 inclusive are diagrammatic views evidencing the operationof the invention.

Turning first to Figs. 1, 2 and 3 there is shown, by way of example, aradio receiver adapted for radio direction finding as well asconventional radio reception. One form of radio direction findingapparatus to which such receiver is adaptable includes a rotatable loopantenna for sensing the direction of the transmitted signal upon which abearing is based and a fixed antenna for resolution of signal ambiguity,as is well-known. Moreover, the apparatus is indicated as capable of useas a range receiver in the beacon band, for reception of very highfrequencies, and for ordinary broadcast reception.

Function selection is obtained by means of a handle in operable to sixpositions as shown in Fig. 3. For convenience these are designated as A,B, C, D, E and F reading counterclockwise, although it will beunderstood from what follows that the number of functions is not limitedto six, but may be more or less, and in any desired grouping.

At position A the receiver is set to the rotatable loop of the aircraftand in position B to the fixed antenna, tuning being accomplished oneither position within the band of 545 to 1700 kilocycles.

At position C the receiver is connected to an antenna for receiving veryhigh frequencies and tuning is accomplished in the band of 108 to 122megacycles.

At position D the receiver is set to the loop, at E to marker beaconrange finding, and at F to voice reception, all three operableselectively in the band of 200 to 450 kilocycles.

3 tent device (not shown) as is well known in the art. A shaft I3 of theswitch I2 carries the handle I0. Switch I2 is supported on a face plateI4, there being an aperture therein for passage of the shaft I3.

The variable condenser or equivalent device for tuning within a selectedfrequency band is indicated at IT, and is provided with a control shaftI8 to which is secured the knob I9 for rotation of the shaft I8 in theconventional manner.

Since the tuning device I1 i effective on any of the bands for which thereceiver is designed the dial 2| (Fig. 7) is graduated into threeconcentric sets of indicia 23, 24 and 25 representative of the threebands embraced in positions A and B, C and D, E and F respectively. Dial2| is provided with a hub 21 (Fig. 6) and set screws 28 wherebyattachment thereof to the shaft I8 is effected.

In order to expose only that one of the scales 23, 24 and 25 ofimmediate consequence a shutter 3| is provided, and comprises a thin,flat, circular member having three arcuate, concentric slots 33, 34 and35 therethrough, each of which is adapted to be placed in register witha scale 23, 24 or 25 respectively upon appropriate partial rotation ofthe shutter. Shutter 3| is mounted for free rotation on the shaft I8 bya hub 36, this latter also having secured thereto a pinion 31 and pinionside plates 3838.

The conventional fixed tuning hair line 4| is shown as part of a window42 set into a suitable opening in the front escutcheon plate 43 whichalso carries the legends A to F inclusive.

Rotation of the shutter 3| to any of its three positions is through themedium of mechanism now to be described.

Afiixed to the shaft I3 is a substantially circular disc 45 having asingle gear tooth 46 protruding from a chordal portion thereof, thepitch circle of the tooth being co ncident with the peripheral circularportion of the disc.

Coplanar with the disc 45 is the slidable member 41 including twoconcave ed e portion 48 and 49 interrupted by a notch 52 adapted to meshwith the tooth 46. The radius of each of the portions 48 and 49 is equalto that of the disc 45 and the disc is in mutually sliding contact withone or the other during certain portions of the function cycle.

Member 4! also includes the rack 54 in mesh with the pinion 31. In orderto retain these two elements in en agement there is provided (Figs. 6and 8) a retainer 55 including an apertured ear 51, o posed resilientears 58-58, a protuberance 59. and an upturned lip 6|. Ears 5858 pressmem er 4'! upwardly to maintain inion 31 and rack 54 in mesh.Protuberance 59 cooperates in the maintenance of s ch engagement andprovides a line-contact guide for the rack 54. Lip EI and ear betweenthem guide the rack 54 laterally, the plates 3838 assisting therein.

To preserve alignment of the member 47 and disc 45 a U-shaped guard 63'(Figs. 1 and 5) is riveted or otherwise fastened to the member 41, theupstanding sides of the guard embracing a portion of the disc 45 in anyof the operative positions of the member 41.

In order to maintain proper engagement of the edge of member 41 with theedge of disc 45 a support 65 (Figs. 1 and 4) is secured to the plate I4.Referring particularly to Fig. 4 the support 65 includes an attachingportion 66, an arm 61 and furcations 68 and 69 extending oppositelytherefrom. Furcation 68 is resilient and includes a pair of upstandinglugs Ill-I0 adapted to guide the guard 63 therebetween. Acting as abackstop for the furcation 68 is the finger 7| formed as a, continuationof the portion 66. Furcation 69 is likewise resilient and terminates ina hump or detent 12 adapted to engage and temporarily look into any ofthe three notches 13, 14 or 15.

Assuming the parts to be in the position shown in Fig. 3 with the handleI0 at its extreme clockwise position, corresponding to legend A, thereceiver is adjusted to receive on the loop in the band of 545 to 1700kilocycles. The scale 23 will be exposed by shutter aperture 33, now inregister with window 42, and the shutter-shifting mechanism is as shownin Fig. 9. A circular portion of disc 45 will be lying in concavedepression 48 of member 41 thereby locking the shutter 3| in thatposition but permitting rotation of disc 45. Moreover detent 69 isengaged in notch 73 to insure further against accidental movement ofmember 41. With aperture 33 in position dial scale 23 only may beutilized in tuning by means of knob I9.

Rotation counterclockwise of handle ID from position A to position B mayoccur simply by rotation of the circular portion of disc 45 withinconcavity 48, such movement being ineffective to actuate member 41 (Fig.10). Tuning may be performed in the same band by means of knob I9, theswitch I2 having merely modified the circuitry from loop to antenna.

Further counterclockwise rotation of handle ID from position 13 toposition C engages tooth 46with notch 52 to move switch I2 andsimultaneously to actuate member 4! to the right (Fig. 11). Detent 69 isdislodged from notch 13 and. will snap into notch 14. Through rack 54and pinion 3'? the shut er 3! is thus rotated to bring aperture 34within the window 42 and in radial alignment with scale 24. Detent 59insures accurate and positive register of aperture 34. Tuning may now beaccomplished with the circuitry as modified by change in position ofswitch I2 and through the medium of scale 24.

Movement of switch I2 from position C to position D will cause tooth 45to move member 4! further to the right (Fig. 12) and to shift engagementof detent 59 from notch I4 to notch 75. Simultaneously aperture 35 isbrought into operative relation with scale 25.

Additional counterclockwise rotation of switch I2 from position D toposition E or from E to F is ineifective to operate member 47, thecircular portion of disc 45 merely sliding relatively to concavity 49(Figs. 13 and 14). Tuning may be accomplished through scale 25 on any ofpositions D, E or F as desired.

Step-by-movement of switch I2 in a clockwise sense constitutes merely areversal of the sequence illustrated in Figs. 9 through 14.

From the foregoing it will have been comprehended that I have provided asimple, positive mechanism which simplifies to a great degree theselection of a desired circuit arrangement together with the desiredselection of tuning scales. The construction is such as to be foolproofand reliable, both desiderata being of paramount importance in aerialnavigation.

While I have shown a particular embodiment of my invention, it will beunderstood, of course. that I do not Wish to be limited thereto sincemany modifications may be made, and I therefore contemplate by theappended claims to cover any such modifications as fall within the truespirit and scope of my invention.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. Function selecting mechanism for a radio receiver or the likecomprising a first member rotatable to any position in a plurality ofgroups of positions, a second member rotatable to a plurality ofpositions equal to the number of said groups, a disc secured forrotation with said first member and having at least one tooth extendingradially thereof and a circular peripheral portion, a, member mountedfor sliding movement relatively to said disc member and having a notchadapted to be engaged by said tooth and concavities adapted to receivesaid circular disc portion, and means interconnecting said second memberand said sliding member, engagement of said tooth and notch uponrotation of said first member being effective to rotate said secondmember, and disengagement thereof permitting rotation of said firstmember independently of said second member.

2. Tuning and function selecting mechanism for a radio receiver or thelike having a plurality of circuit components, comprising a circuittuning device, switching means for changing the arrangement of thecomponents to enable reception by the receiver within a selected one ofa plurality of frequency bands and for selecting functions within saidbands, a tuning dial associated with said device and bearing a pluralityof scales, one individual to each said band, a movable shutter having aseries of apertures each being adapted to expose the entire range ofeach of said scales singly and selectively, a function selector switch,and means interconnecting said shutter and switching means to actuatesaid shutter upon movement of the switching means to predeterminedfunction positions.

3. Mechanism as in claim 2 in which said interconnecting means includesan intermittently operating linkage.

4. Mechanism as in claim 2 in which said interconnecting means includesa substantially circular disc operable with said switching means, aprojection carried by said disc, a slidable member having arcuate edgeportions adapted for sliding movement relatively to circular portions ofsaid disc and a notch engageable by said projection, said member beingoperatively connected to said shutter.

5. Tuning and function selecting mechanism for a radio receiver or thelike having a plurality of circuit components comprising a circuittuning device, a rotatable switch for changing the arrangement of thecomponents to enable reception by the receiver within a selected one ofa plurality of frequency bands and for selecting functions within saidbands, a tuning dial associated with said device and bearing a pluralityof scales, one individual to each said band, a rotatable shutter havinga series of apertures each adapted to expose said scales singly andselectively, a plate secured for rotation with said switch and having atleast one circular peripheral portion and at least one radial tooth inaxial alignment with said portion, a member mounted for sliding movementperpendicularly to the axis of said disc and having a plurality ofconcavities adapted to be moved into sliding engagement with saidportions, each pair of concavitie being interrupted by a notch adaptedto be engaged by said tooth, said member carrying a rack and saidshutter carrying a pinion with which said rack is in mesh.

WILLIAM POWELL LEAR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,356,915 Fisher Oct. 26, 19201,615,041 Ross Jan. 18, 1927 1,619,544 Sanford Mar. 1, 1927 1,711,931Farrington May 7, 1929 1,726,876 Asbury Sept. 3, 1929 1,761,211 Jones eta1 June 3, 1930 1,807,995 Marvel June 2, 1931 1,833,235 Slocumb Nov. 24,1931 1,958,282 Tregenza May 8, 1934 2,039,885 Chum May 5, 1936 2,118,859Newman May 31, 1938

